998 CONTRIBUTIONS FEOM THE NATIONAL, HERBARIUM, 



79. Neomammillaria denudata (Engelin.) Britt. & Rose, Cactaceae 4: 129. 

 192.3. 



Mammillaria lasiacantha denudata Engelm. U. S. »& Mex. Bound. Cact. 5. 

 1859. 



Coahuila. Texas. 



Globose, 2.5 to 3.5 cm. in diameter ; tubercles 5 to 6 mm. long ; spines 50 

 to 80, glabrous or nearly so, 3 to 5 mm. long, the innermost usually much 

 shorter ; flowers and fruit from near the center but not from the axils of 

 young tubercles ; flowers 10 to 12 mm. long ; perianth segments about 12, ob- 

 long, obtuse, the margins white, the center light purple ; fruit clavate, red, 

 1.5 to 2 cm. long; seeds black. 



80. Neomammillaria lenta (K. Brandeg.) Britt. & Rose, Cactaceae 4: 129. 

 1923. 



Mammillaria lenta K. Brandeg. Zoe 5: 194. 1904. 



Coahuila, the type from Viesca. 



Described as cespitose ; individuals globose to short-cylindric, almost hid- 

 den by the white delicate spines ; tubercles very slender, light green ; spine 

 areoles naked ; spines about 40, very fragile ; axils woolly and occasionally 

 bearing a single bristle ; flowers whitish, 7 mm. long ; perianth segments 

 pointed ; fruit red, clavate ; seeds 1 mm. in diameter, dull black. 



81. Neomammillaria Candida (Scheidw.) Britt. & Rose, Cactaceae 4: 130. 

 1923. 



Mammillaria Candida Scheidw. Bull. Acad. Brux. 5: 496. 1838. 



Mammillaria spJiaerotricha Lem. Cact. Hort. Monv. 33. 1839. 



Mammillaria humboldtii Ehrenb. Linnaea 14: 378. 1840. 



Central Mexico ; type from San Luis Potosi. 



Cespitose; individual plants globose, 5 to 7 cm. in diameter, almost hidden 

 by the white spines; radial spines numerous, radiating; central spines 8 to 

 12, porrect, often brownish at tip, a little stouter than the radials; axils 

 setose; flowers 2 cm. long, rose-colored; perianth segments serrulate toward 

 the apex ; fruit red ; seeds black. 



82. Neomammillaria vetula (Mart.) Britt. & Rose, Cactaceae 4: 130. 1923. 

 Mammillaria vetula Mart. Nov. Act. Nat. Cur. 16: 338. 1832. 



Hidalgo; type from San Jos§ del Oro. 



Plant somewhat club-shaped, 4 to 5 em. high; tubercles terete, light green, 

 somewhat shining; axils naked or sometimes with a small tuft of wool; 

 radial spines about 25. spreading, white, bristle-like; central spines 1 to 6, 

 stouter than the radials, brownish; flowers 12 to 15 mm. long, borne at up- 

 per part of the plant; outer perianth segments red, with yellowish mar- 

 gins, the inner cream-colored. 



83. Neomammillaria fertilis (Hildm.) Britt. & Rose, Cactaceae 4: 131. 1923. 

 Mammillaria fertilis Hildm. ; Schum. Gesamtb. Kakt. 530. 1898. 

 Mexico, the range not known. 



Cespitose, the individual plant globose to short-cylindric, dark green; 

 tubercles arranged in 8 or 13 rows, a little woolly in their axils; radial 

 spines 7 to 10, acicular, 6 mm. long; central spines 1 or 2, straight, stouter 

 than the radials, 10 mm. long; flowers deep crimson, 2 cm. long; inner 

 perianth segments linear-lanceolate, acute. 



